A method for manufacturing electrode sheets is disclosed, for example, in Patent document 1. As described in the patent application, a belt-shaped member in which an active material layer has been formed on a collector is cut, while being conveyed, in the conveying direction. A plurality of cutting blades are arranged in the traveling direction of the belt-shaped member, the central portion in the widthwise direction of the belt-shaped member is first cut and then battery electrodes positioned at both side portions of the belt-shaped member are finally cut. As a result, the appearance of burrs at the end surface of the electrode can be prevented.
Further, Patent document 2 discloses a technique for manufacturing electrode sheets in which an electrode material is coated in stripes on a belt-shaped collector perpendicularly to the lengthwise direction, so that uncoated sections remain in a predetermined gap between the stripes and the belt-shaped collector is slit in the widthwise direction.
Patent document 3 describes an invention relating to a mechanism that adjusts a tension of a pass line of a nickel-plated felt that arrives from a pressurizing device into a drying device via a coating device. More specifically, a configuration is disclosed in which a pre-tension imparting means and an after-tension imparting means that impart a constant tension are provided in a pass line before and after the coating device.
Further, Patent document 4 discloses an apparatus that corrects distortions in the thickness direction of an electrode sheet.
[Patent Document 1] Japanese Patent Application Laid-open No. 2003-68288.
[Patent Document 2] Japanese Patent Application Laid-open No. H9-45313.
[Patent Document 3] Japanese Patent Application Laid-open No. H9-63578.
[Patent Document 4] Japanese Patent Application Laid-open No. 2002-234229.
The inventors considered the possibility of obtaining a plurality of electrode sheets, as shown in FIG. 1, from an original sheet 1 that has a plurality of coated portions 11, 12, 13 coated with an electrode material in the lengthwise direction with a predetermined gap on a wide belt-shaped metal foil 10. In the original sheet 1, the electrode material 11, 12, 13 is coated on the metal foil 10 with a predetermined gap and dried. Then, the original sheet 1 is rolled with rollers and the density of the electrode material 11, 12, 13 is increased. The original sheet 1 is cut along cutting lines z1 to z5 that are set in the lengthwise direction on the coated portions 11, 12, 13 coated with the electrode material and in the portions between the coated portions 11, 12, 13 (uncoated portions 18, 19). As a result a plurality of electrode sheets can be manufactured with good efficiency.